In video systems, there is often a need to convert between video information communication formats. For example, a source of video information (e.g., a movie system) may record and provide video information in a different format than the destination of the video information (e.g., a home television system) can process. For example, a movie system may supply video information at a rate of twenty-four full frames per second, while a home television system may only be able to process an interlaced stream of sixty video fields per second (i.e., thirty pairs of top and bottom fields per second). One technique used to translate twenty-four frames/second to 60 fields/second includes converting each original frame to a top field and a bottom field transmitted consecutively, which yields 48 fields/second. Then after every fourth field, a duplicate field is inserted, which yields a final rate of 60 fields/second. This technique may be referred to as 3:2 pull-down, and the duplicate field may be referred to as a pull-down field.
Video systems that utilize the insertion of pull-down fields typically provide top and bottom fields from a single video frame, and accordingly, corresponding top and bottom fields represent an image at a single instance in time. Based on this, the receiver of such information may process corresponding top and bottom video fields to produce a single high-quality video frame. Since the existence of pull-down fields in a received stream of video fields is a indication that the received stream of video information may be so processed, detecting the existence and location of pull-down fields may be advantageous.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with the present invention as set forth in the remainder of the present application with reference to the drawings.